Maple Bladder Gall Mite
Maple Bladder Gall Mite
Maple bladder gall mites are most common on silver maple and to a lesser extent, red maple.
The mites overwinter in protected places in the bark on tree trunks. In the spring they move to the developing leaves. The mites feed on the underside of the leaves which then form the galls that enclose the mites. The mites lay eggs which hatch and the offspring go to other leaves and cause formation of new galls. By mid-summer the mites have stopped causing new galls.
The galls are round and can be green, red, or black. The leaves closest to overwintering sites are most heavily infested.
The tree is not seriously harmed so no controls are suggested.